Are Carbon Nanotubes Dangerous Like Asbestos?
May 27 at 4:04pm by Aileen
ScienceNews reported last week that research on mice suggests these new fullerene-based wonder-fibers may be as dangerous as asbestos in the environment. The study showed that multi-walled (rigid) nanotube fibers longer than 15 micrometers cannot be removed from sensitive organic tissues by microphages, and that this causes inflammation that could lead to asbestos-like diseases including mesothelioma, a fatal form of cancer.
The study was published in the May 20 online edition of Nature Nanotechnology, and according to the Washington Post serves as a preliminary warning that there may be serious issues with the technology that warrant very careful planning to protect industrial workers, the public and the environment as nanotube fibers become more common in consumer and industrial products.
Companies around the world produce thousands of tons of nanomaterials a year, not all of them in the form that poses the threat identified by these researchers. Nanotubes alone are expected to become a multi-billion dollar industry within the next few years. While the government pumps about $1.5 billion a year into R&D for nanotechnology, only about 5 percent of that goes into health and safety concerns.
It would be quite refreshing if, for a change, we incorporated the lessons of history as we develop this promising new technology to forestall issues related to health, safety and environmental pollution before they become just more grim statistics attached to greed over due caution. And for this reason the situation bears watching to see if identified areas of concern are simply denied and swept under a profit rug, or rationally dealt with as if humans could accept responsibility - and minimize risks - per the less than hopeful side-effects of our intelligent designs.
What Happens To Your Anti-Bacterial Soaps
May 20 at 5:05pm by Aileen
The “germ-free” craze not only contributes to a generation of homebound children who have no developed resistance to real world ‘germs’ or irritants, we’ve also been warned over and over again for more than a decade that those bacteria we’re fighting will themselves develop resistance to the anti-biotics we use against them. Now a study by the Biodesign Institute at Arizona State University has traced the active ingredients in antibacterial soaps to their final resting place in the shallow sediments of estuaries into which treated wastewater is dumped.
The active ingredients traced are triclosan (TCS), which is structurally similar to dioxin, and triclocarban (TCC), a closely related compound. Biodesign Institute researcher Rolf Halden and coworkers traced these compounds to the shallow sediments of New York City’s Jamaica Bay and the Chesapeake Bay, the world’s largest estuary. Both of these compounds operate as endocrine (hormone) disruptors in mammals, much as agricultural chemicals operate to disrupt the sexual development of amphibians in the midwest.
Halden made use of concentrations of radioactive fallout from nuclear testing in the last half of the 20th century to determine how long ago the antimicrobial residues were deposited (and thus how long they’re lasting in the environment). And while core samples determined that a 1978 improvement in a Baltimore waste treatment plant did drop the levels of deposited TCC, the upgraded technology just put more of the substance into the sewage sludge that is disposed of by being applied as “fertilizer” on agricultural cropland.
Halden is planning to continue his research and study body burdens and health effects in pregnant women, nursing mothers and infants. Ecologically speaking, we are probably better off living with a few germs, and hand washing with regular soap has been shown to be just as effective as with antimicrobial soaps in sanitizing hands. Yet another good reason to reconsider our fear of germs - sometimes, it seems, the cure is worse than the disease.
Holy Hitchcock, Batman!
May 14 at 6:06pm by Aileen
More ‘Weird Science News’ today. Seems that the burgeoning raven population in the UK - where ravens were once very rare and are still a protected species - has recently taken to forming large gangs and killing farm livestock in Scotland, Wales and some parts of England.
Now, ravens are the smartest of birds. According to scientific researchers, they’re right up there with dogs and primates on the intelligence scale, and like some parrots can even learn to speak human languages. Just ask Edgar Allen Poe! And while ravens are carrion-eaters mostly, they are known to be birds of prey that will attack rabbits and other small critters. Their beaks are sharp and sickle-shaped, their talons are muscular. They get to be about two feet long, and are extraordinary aerial acrobats. They are also the primary bad guys in Daphne du Mourier’s classic horror novel The Birds, as made into the film classic of the same name by Alfred Hitchcock. There have been some B-movie reprises too, though they shall remain nameless (so as not to reveal my personal addiction to B-grade horror movies).
We get raven gangs here in the southern Appalachians. During one memorable grandchild birthday party they descended to steal as many of a scattered bag of lemon drops as they possibly could, then became furious when those hard candies stuck their beaks together with a mass of yellow goo. We laughed and laughed, they didn’t think it was the least bit funny. Probably a good thing they didn’t decide to attack, now that I know they’re killers!
Check out the story from Britain’s Daily Mail about these killer raven gangs. Seems farmers are losing their newborn lambs as fast as they’re born, and now the ravens have started going after calves and even full-grown sheep!
While I suspect recent UK policies to immediately cremate dead livestock (imposed due to fears of Mad Cow and such) has led to some hungry ravens doing whatever they have to do to survive without ready carrion, I hope they don’t decide to decimate raven populations again. These really are spectacular birds.
Evolution’s Practical Joke is Still Funny
May 12 at 6:06pm by Aileen
…after all these years
That great practical joke that life’s designer [be it blind nature or purposeful god] played is still with us to confound orderly notions of biological evolution. The genome of Australia’s duck-billed platypus has been sequenced by an international group of scientists led by researchers at Washington University School of Medicine in St. Louis.
The venomous, egg-laying, duck-billed, web-footed, beaver-tailed mammal is one of the earliest offshoots of the mammalian lineage from when it split off from primitive ancestors some 166 million years ago. The genome confirms the chimeric status of this odd animal which displays traits of reptiles, birds and mammals.
As part of their analysis, researchers compared the platypus genome with human, mouse, dog, opossum and chicken genomes. Chicken genome was chosen because it represents a group of egg-laying animals that includes extinct reptiles that passed on much of their DNA to mammals over the course of evolution. When analyzed, the genetic sequences for venom production in the male platypus was found to have arisen from duplications in a group of genes evolved from ancestral reptilian genomes. They hypothesize that duplications in those very same genes led to the evolution of venom independently in modern reptiles.
The project involved sequencing about 2.2 billion base pairs and 18,500 genes. The Platypus has 52 chromosomes and an unusual 10 sex chromosomes. The platypus X chromosome also bears a striking similarity to the sex chromosome of birds.
Final conclusion? The duck-billed platypus is just as bizarre a mix-and-match critter genetically as it appeared to be when the first specimens were shown to the scientific community some 200 years ago. Skeptics then believed the animal was someone’s idea of a practical joke hoax. Turns out it really is a genetic practical joke, but it comes as-is in nature.
Links:
Platypus Genome Explains Animal’s Peculiar Features
Daily Mail: It’s a bird, it’s a beaver…
Surprise! Human Babies Should Drink Human Milk
May 7 at 6:06pm by Aileen
Michael Kramer, a professor of pediatrics at McGill University reported this week that breastfeeding raises children’s IQ and improves their academic performance later in childhood.
Their study evaluated children in 31 Belarusian hospitals and clinics. Half of the women were directly encouraged to breastfeed exclusively, the other half did things the ‘normal’ way (for Belorussia). Six and a half years later the children’s IQs were tested and their teachers submitted academic performance ratings. Scores on both were significantly higher for the children of women encouraged to breastfeed, though there is no indication that the researchers confirmed how many of those mothers actually did breastfeed or for how long.
“Our study provides the strongest evidence to date that prolonged and exclusive breastfeeding makes kids smarter,” Kramer said.
Read the rest of this entry »
Where Have All the Salmon Gone?
May 5 at 4:04pm by Aileen
A declaration of commercial fishery failure by Commerce Secretary Carlos Gutierrez has paved the way for Congress to allot funds for alleviating financial hardship among the West Coast’s commercial Chinook salmon fishing industry off California and Oregon. The crisis has been building steadily every year since 2000, culminating in this latest action - the commercial salmon fishing industry has essentially been shut down.
National Oceanographic and Atmospheric Administration [NOAA] researchers suggest that changes in ocean conditions - possibly due to global warming - are to blame, along with loss of freshwater habitat for salmon spawning, a chronic problem.
There will be some coho salmon fishing allowed off the coast of Washington and northern Oregon, but there will be financial hardship in that industry as well due to strict limits. This crisis has been building for years, attempts along the way to mitigate it have proven to exacerbate the situation, such as the introduction of farmed salmon. Fish stock collapses in traditionally abundant fisheries off both coasts and elsewhere in the world bode ill for the seafood component of the human food supply, just as the worldwide food crisis heats up around the world for staple crops like corn and wheat and rice.
We could be beyond a tipping point right now, and things could get a bit more than just ‘interesting’ over the next months. Will science be able to come to the rescue, or will it remain helpless to mitigate the collapse of world food supplies? Stay tuned…
Links:
“Fishery Failure” Declared for West Coast Salmon Fishery
Hatchery Controversy Takes on New Significance as Wild Chinook Populations Crash
Escaped Farmed Salmon Infiltrate Fitter Wild Populations
Dramatic Declines in Wild Salmon Populations Linked to Farmed Salmon
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